Hydraulic press.



PA'IENIEDi JULY 23, 1907.

W. ASTPALGK. HYDRAULIC PRESS.

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No. 860,958. PA'IBNTED JULY 23, 1907.

W. ASTFALCK.

HYDRAULIC PRESS.

APPLIOA'IION FILED 00T.119| 1906.

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UNITED STATES WILND ASTFALCK, OF TEGE-L, NEAR BERLIN, 'GERMANY- HYDRAULIC PRESS.

No. l860,958.

Specification of Letters Patent.

'Patented July 23,1907.

Application mea octoter 19,1906. serial No. 339,704.

To all Iwhom 'itmay concern: I

Be it known that I, WILAND As'rr'ALoK, a citizen' of the German Empire, and a resident of Tegel', near Berlin,.Germany, have invented certain new and useful Improvements in Hydraulic Presses, of which the following is a specification.

This invention relates to an apparatus for filling and discharging the press cylinder or cylinders of hydraulic presses under pressure. i

In my improved apparatus the feed press cylinder -is taken directlyfrom a separate supply cylinder having a piston which isgeared with the hydraulic piston, and when the pressing operation'is completed the feed water is returned to the supply cylin- .der to be used over again.A During the idle motion of the hydraulic piston the feed Water will thus be forced by the piston f the supply cylinder into the presse-ylinder, which action may be assisted by a suction action of the hydraulic piston, and during the ,return movement of the hydraulic piston the feed water is displaced by the same and sometimes drawn in by the supply piston.

In order to provide for losses of water arising, for instance, from leakage, the supply piston may have a somewhat larger diameter and the supply cylind'er be connected to a vessel for the water under pressure, so that the supply piston will dis'placeor draw in more than the press cylinder is capable of receiving or discharging and the difference will be returned to or withdrawn from the said vessel under corresponding pressure.

The respective cutting-off members may act automatically or be operated positively each for itself and partly by mechanical means and partly by a liquid pressure medium, or however all thecutting-off members may be operated positively from one source,`if desired. The construction and operation of the controlling members4 have therefore no bearing on the gist of the present invention.

The accompanying drawing shows by way of example some constructional forms oa hydraulic press with the hereindescribed improvement. A

' Figures l and 2 are longitudinal sections of such a press in two different working positions. Fig. 3 is a plan and Figs. 4 and 5 are longitudinal sections of two other forms of construction.

` Similar letters refer to similar parts throughout the several views. 1

According to the construction' shown in Figs. l to 3, the hydraulic press cylinder a communicates through a channel b with a superposed supply cylinder c. Both pistons d and a arel connected by'rods' f, secured to the .traverse or yoke f of the piston eon the one hand and Awater for the.

I to the press plate f 2 of the piston d on the other; There is arranged in the channel b an outwardly positively operatedrvalve g .which opens towards the hydraulic press cylinder. Further, a pipe h leading to the vessel l for the water under pressure branches from the chau-l nel on the one hand and on the other hand a high prossure pipe k adapted-.to be closed by a controlling momber i. vThe return 'or upward moyement ol' the partsf fl f 2 with the-two pistons e d is effected by their-@turn cylinders m,- the pistons p movingtherein boing counected to the press plate f2. Both return-cylinders communicate on the one hand with the high pressure pipe k through a pipe'q and a controlling -menibcr s and onv the other hand with the discharge pipe t. I t' the controlling member s is in the position as' indicated in Fig. l and consequently the pipe q i n communication piston-.and the rods'can perform its downward movement, as the gravity of these parts.. is sufficient for producing the said motion.- The downward movement of these parte takes place to such an extent asis `permitted by the compactness ofthe work u to be acted on bythe forces the fluid contained lin the cylinder c through the w. plus of the fluid then escapes through the pipe h into the vessel l.. During this action, the high pressure pipo k must, of course, be closed bythe controlling member i. When the filling of the press cylinder isfinished,

controllingmernber g previously closed; the controlling member s'remains open. The water under pressure fed through the pipe and entering the press cylinder a is now'effective and forces the press piston dl downwards to such an extentthat the desired pressure of the work or hlank u takesplaceil The supply piston e also takes part in the movement of the press piston; the water vessel l. A f

When the pressing operation is finished, the controlling member assume the position indicated in Fig. l, the controlling member g will be opened and the controlling member s so adjusted that the water und or high pressure can pass through the vpipe q -into the rcturn-cylinder 'm so -as to move the. return-piston n with the vpress ram' and supply' piston .e upwards. The water displacedA by the press piston enters the cyl iudcr c. As howevelthe piston e leaves more space than th is with the pipe t, 'the Water can then pass out ofthe return-cylinders and the press piston with the supply channel b and the opened valve int-o the press cylinder l a. The valve g is opened for instanceby a hand lever 1f the piston e is larger than'the pistonl d, thopsurtheicontrolling member 1I will be opened (Fig. v2) but the displaced from the cylinder -c may however-'enter the fluid can occupy, the Wanting fiuid may bersupplied press-rama). Fig. 2 shows-this position.A During this downward movement, the piston e acts as plunger andv from the vessel l. If a separate vessel is not provided, i ,the pistons d, e should 'then have the same diameter in order that the displaced Huid Will exactly conform with that supplied; For practical reasons, a rising pipe It willhowever always-be provided, in which a liquid column of a vcertain pressure is contained so Vas tol counterbalance the unavoidable differences in the quantities or volumes of water.

In the construction according to Fig'. 4, the two pistons rl, e are directly connected by a rod f3 arranged within the cylinders a, c.. If a simple back pressure valve is used instead of the controlled valve g, the controlling member -i should then be provided with a branch pipe o and a valve n inserted in the rising pipe h. said valve n being regulated during the pressing operation so as to enable a discharge of the water dis placed by the pistone in the cylinder c. This valve n may be of such a construction that it will open automatically during the upward stroke o t'the piston e, but be opened and kept open during the pressing operation bya piston r arranged in the cylinder :t communicating .with the high pressure pipe. If in this'orm of construction the press piston rl is 'moved downwards, the piston e will then force the water contained in c through l the valve g into the cylinder a. If the press piston is moved upwards, the controlling member t" should then be previously adjusted in such a manner that the pipe ,Isl communicates with the pipe o and the Water displaced by the press piston may be discharged through o. The piston c however.simultaneously draws a fresh quantity oi water from the rising pipe h through the valve n. which automatically closes under the action of a spring z. i

In tliciorm of construction according to Fig. 5, one single cylinderv is provided which acts on the side c as a suppl y cylinder and on the side a as a press cylinder. Consequently, there is but one piston provided. The

`two cylinder halves likewise communicate with each y l and the controlling member i opened, so that the fluid the rising pipe h.

l 'do not herein claim specifically the embodiment shown in Fig. 5 as the same forms the subject matter of a divisional application, Serial No. 368,476, filed April i6, 1907 vthe cylinders, and 1neans.1'or

What I claim as my invention and desire to secure by United States Letters Patent .is-

1. '.lhe combination willi the press chamber, the supply chamber, and the means providing communication between said chambers, ot' means reciprocating in said chambers and exeuting pressure on the fluid in the chambers alternately during its reciprocation to cause the tluid to pass under pressure alternately from one of said chambers to l the other.

2. The combinationof the press chamber, the supply chamber` the means providing communication between said chambers, the reciprocatory supply and press pistons connected to move in unison and coiperating to cause the uid to alternately pass u-nder pressure from one of said chambers to the other when the pistons move to and from pressing` position. and meansv for vsupplying pressure to the fluid to act on the driving face of the press piston when the pistons have reached pressing,r position.

Si. In au apparatus of the character described. the combination with the press-cylinder and the press-piston working therein, of a supply cylinder, means providing coinmunication between the press-cylinder and the supply cyl: inder. a supply piston working in the supply cylinder'. means connecting the supply piston to the press-piston to cause them to move in unison whereby the down-stroke of the press-piston causes the supply-piston tori'orcc fluid under pressure from the supply cylinder' to the press-CyL inder and the lip-stroke of the press-piston forces the fluid' back to the supply-cylinder, andmeans for supplying,r pressure to the fluid in the pres cylinder when the' press-pistou has reached pressing position.

4. In an apparatus ot' the character described, the combination with the press-cylinder and the press-piston working thercin. of a su1 )ply eylimler having :l piston, means providing communication between the` press-cylinder and the supply cylinder', connection between the press-piston and the supply piston whereby the down-stroke of the "presspiston causes fluid to pass under pressure from the supply cylinder to the press-cylinder und the lip-stroke of the press-piston causes the fluid to Iiow back to the supply cylinder. and means for supplying pressure to the fluid in the prcsscylinder when the press-pistou has` reached pressing position.

5. ln un apparatus of the character described. the combination with the press-cylinder aud'lhe presspiston Workini,Il therein. of a supply cylinder' of a diameter different from that of' the press-cylinder, means providing com municalion between the press-cylinder and .the supply cylinder. :i supply piston working in the supply cylinder. means connecting the suppl,\'piston to the press-piston to cause the pistons to move in unison whereby the downstroke of the press-pistoncauses the supply piston to force (luid under pre. sure l'rom the supply cylinder' to thepresscylinder and the upstroke of the p'r piston'forces fluid from the press-cylinder to the supply cylinder. ineans for receiving from or supplying t0 the cylinders the excess or shortage of fluid caused -by the difference in diameter of supplying pressure to the liuld in the 'press-cylinder when pressing position.

The foregoing specification signed at Berlin this sixth dayoi October 1906. l

WILAND AS'IFALCK.

the press-pislouhas reached' 

